There was a program on Dutch National Television on Internet addiction. In that program one of the platforms positioned as addictive was Twitter. Ridiculed as a platform to throw brain farts around, the mostly older generation talking heads completely failed to see the bigger picture of tools like twitter.
There obviously is a real downside to these messaging tools, as they can contribute to Internet Addiction as described by Jerald J. Block, M.D. in Psychiatry online
To quote: “Internet addiction appears to be a common disorder that merits inclusion in DSM-V. Conceptually, the diagnosis is a compulsive-impulsive spectrum disorder that involves online and/or offline computer usage (1, 2) and consists of at least three subtypes: excessive gaming, sexual preoccupations, and e-mail/text messaging (3). All of the variants share the following four components: 1) excessive use, often associated with a loss of sense of time or a neglect of basic drives, 2) withdrawal, including feelings of anger, tension, and/or depression when the computer is inaccessible, 3) tolerance, including the need for better computer equipment, more software, or more hours of use, and 4) negative repercussions, including arguments, lying, poor achievement, social isolation, and fatigue”

On the other hand messaging tools are a substitute for the banter and terse information exchange that normally occurs in the office or the workshop and help to fight social isolation.
I live in a more remote area from our office and having tools such as twitter, skype, msn actually help to stay connected without the necessity to physically meet people. IMHO tools like twitter or the closed community variant yammer can contribute to CO2 reduction and family time in general!
As Capgemini NL is currently working on a concept called Capgemini 3.0 where Capgemini is working with customers on a model to encourage consultants to work at home in order to reduce commuting. I think a yammer like environment would be a good enhancement of the standard working toolset for a lot of commuting consultants.
The solution for the addiction being to regularly switch of the texting stuff and spend time with your family 😉